Charter schools under assault by Mayor de Blasio have found a political champion: state Senate Republican leader Dean Skelos.

Skelos vowed to address the plight of charter schools — which have been denied classroom space and capital dollars by de Blasio — as part of state budget talks with Gov. Cuomo and state lawmakers.

“What the mayor is doing is unconscionable,” Skelos told The Post Sunday.

Skelos said he was outraged by de Blasio’s decision to cancel classroom space for three of longtime adversary Eva Moskowitz’s Success Academy charter schools this fall that were approved last year by former Mayor Michael Bloomberg. The schools were supposed to share space, or be co-located, in city school buildings.

And Skelos said he was equally troubled by de Blasio’s decision to scrap a $210 million construction fund used to build space for charter schools, as well as his plan to charge better-financed charter schools rent.

“We’re going to look at all options,” said Skelos (R-Nassau). “In our government anything can be done if there is a will to do it. I sure have the will. Absolutely.”

Skelos said he was particularly irate about de Blasio’s decision to make the Success Academy Harlem Middle School homeless. Space for two other new Success Academy charter elementary schools — scheduled to co-locate in high school buildings in lower Manhattan and Queens — were also yanked by the mayor.

“He’s robbing the opportunity for 600 mostly minority students from getting a quality education,” Skelos said. “We will have conversations with the objective to keep these schools open.”

Skelos noted that the Harlem Academy’s fifth-graders had the highest math scores in the entire state.

“Why would you pull the rug out from under a school whose students are achieving? To not allow them a path to continue is just wrong. It’s appalling.”

De Blasio defended the co-location decisions as equitable and fair when taking into account the needs of students from other schools. He noted that 14 out of 17 charter co-locations were approved, including five out of eight of Moskowitz’s.

But Skelos said the city’s education policy has taken a turn for the worse.

“In the past, the city closed low-performing schools and promoted achieving schools,” he said. “Now we have a mayor who wants to close high-achieving schools and keep open low-achieving schools.”